Effect of fluoride on bone metabolism in rats / 中国地方病学杂志

ABSTRACT

Objective To study the effect of fluoride on bone metabolism in rats, and to understand the mechanism of pathogenesis of skeletal fluorosis. Methods A total of 80 Wistar rats were randomly divided into 4 groups that included control group (distilled water), low-dose group(NaF, 50 mg/L), medium-dose group (NaF,100 mg/L) and high-dose group(NaF, 150 mg/L), respectively. After being bred for 12 weeks, the rats were put to death (etherization). Incidence of dental fluorosis was estimated, and serum was collected. Radioimmunoassay was employed to detect the levels of osteocalcin (BGP), parathyroid hormone (PTH) and calcitonin (CT), respectively.Colorimetry method was employed to determine the levels of alkaline phosphatase (ALP) and acid phosphatase (ACP). Results Incidence of dental fluorosis between the four groups was significantly different statistically(x2 =82.81 ,P ＜ 0.01 ). The incidence was significantly different(x2 = 22.67, 40.00, 40.00, all P＜ 0.01 ) between low-dose ( 80%, 16/20), medium-dose ( 100%, 20/20), high-dose groups ( 100%, 20/20) and control group (0,0/20),respectively. Serum levels of BGP, PTH, CT were significantly different between the groups(F = 38.614, 20.778,3.023, P ＜ 0.01 or ＜ 0.05). There was no significant difference between the four.groups of ALP and ACP in serum (F = 0.609,2.895, all P ＞ 0.05 ). Serum BGP in low-dose, medium-dose and high-dose groups[ ( 19.60 ± 12.79),(33.41 ± 10.81 ), (39.46 ± 9.51 )mg/L, respectively] was significantly higher than that of the control group[ (7.35 ± 3.22)mg/L, all P ＜ 0.01 ]. Serum PTH in low-dose, medium-dose and high-dose groups[ (72.27 ± 25.38), (67.80 ± 12.01), (106.52 ± 36.37)pmol/L] was significantly higher than that of the control group[(47.08 ± 9.22)pmol/L,all P ＜ 0.01 ]. Serum PTH of the high-dose group was significantly higher than that of the low-dose and the mediumdose groups(all P ＜ 0.01 ). Serum CT in medium-dose and high-dose groups[ ( 13.39 ± 2.07), ( 15.05 ± 4.77)pmol/L ] was significantly lower than that of the control group[ (26.06 ± 28.31 ) pmol/L, all P ＜ 0.05 ] and also significantly lower than that of the low-dose group [ (24.49 ± 14. 10) pmol/L, all P ＜ 0.05 ]. Conclusions Fluoride affects bone metabolism in rats, BGP, PTH and CT play a key role in the pathogenesis of skeletal fluorosis.